Global and local contrast control with brightness and shading adjustment of smart glass display

ABSTRACT

A smart glass display includes a first glass layer, a second glass layer, a display layer, an auto-shading layer and a control module. The display layer is disposed between the first glass layer and the second glass layer and includes an array of light emitting diodes and at least one ambient light sensor. The at least one ambient light sensor is configured to detect a level of ambient light at the display layer. The auto-shading layer includes suspended particle devices each of which configured to selectively provide different levels of transparency. The control module is configured to, based on an output of the at least one ambient light sensor, adjust a transparency level of at least a portion of the auto-shading layer.

INTRODUCTION

The information provided in this section is for the purpose of generallypresenting the context of the disclosure. Work of the presently namedinventors, to the extent it is described in this section, as well asaspects of the description that may not otherwise qualify as prior artat the time of filing, are neither expressly nor impliedly admitted asprior art against the present disclosure.

The present disclosure relates to display devices and more particularlyto transparent display devices with automatic brightness and shadingadjustment.

A display device may include a light emitting diode (LED) array that isarranged on a transparent layer such as glass. Transparent spaces arelocated between pixels of the LED array. As the spacing between the LEDsin the LED array increases, the level of transparency of the displaydevice increases. Smaller scale display technologies such as micro LEDscan be used and provide an opportunity to make increasingly transparentdisplay devices.

The display device may be used with variable levels of ambient light.For example, higher levels of ambient light on a front side or a backside of the display device tend to reduce the contrast of the displaydevice. The lower contrast of the display device in these lightconditions makes content such as images or graphics being displayed moredifficult to see.

SUMMARY

A smart glass display is disclosed and includes a first glass layer, asecond glass layer, a display layer, an auto-shading layer and a controlmodule. The display layer is disposed between the first glass layer andthe second glass layer and includes an array of light emitting diodesand at least one ambient light sensor. The at least one ambient lightsensor is configured to detect a level of ambient light at the displaylayer. The auto-shading layer includes suspended particle devices eachof which configured to selectively provide different levels oftransparency. The control module is configured to, based on an output ofthe at least one ambient light sensor, adjust a transparency level of atleast a portion of the auto-shading layer.

In other features, the at least one ambient light sensor includesambient light sensors.

In other features, the at least one ambient light sensor is integratedin the display layer and is disposed within an outer periphery of thedisplay layer.

In other features, the at least one ambient light sensor is disposedbetween light emitting diodes of the display layer.

In other features, the at least one ambient light sensor is in a samelayer of the smart glass display as the display layer and is disposedoutside of a periphery of the display layer.

In other features, the at least one ambient light sensor includesexterior ambient light sensors and one or more interior ambient lightsensors.

In other features, the display layer is an outward facing display layersuch that an image displayed on the display layer is visible on anexterior side of the smart glass display.

In other features, the display layer is an inward facing display layersuch that an image displayed on the display layer is visible on aninterior side of the smart glass display.

In other features, the control module includes: a comparator configuredto obtain, based on the output of the at least one ambient light sensor,a brightness level; a vehicle message transceiver configured to obtainan image to display on the display layer; and an address driverconfigured to adjust brightness of at least a portion of the displaylayer based on the brightness level and drive the display layer todisplay the image.

In other features, the control module includes: a comparator configuredto obtain a dimming level based on the output of the at least oneambient light sensor; a vehicle message transceiver configured to obtainan image to display on the display layer; an address driver configuredto drive the display layer to display the image; and a shading driverconfigured to drive the auto-shading layer to adjust the transparencylevel of at least the portion of the auto-shading layer based on thedimming level.

In other features, the at least one ambient light sensor includes aninterior ambient light sensor; and the control module is configured toadjust the dimming level based on an auto-shading level and an output ofthe interior ambient light sensor to compensate for an amount ofauto-shading and determine an actual interior ambient light level.

In other features, a smart glass display is provided and includes: afirst glass layer, a second glass layer, a display layer and a controlmodule. The display layer is disposed between the first glass layer andthe second glass layer and includes an array of light emitting diodes,suspended particle devices, and at least one ambient light sensor. Atleast one ambient light sensor is configured to detect a level ofambient light at the display layer. The suspended particle devices areeach configured to selectively provide different levels of transparency.The control module is configured to, based on an output of the at leastone ambient light sensor, adjust a transparency level of at least aportion of the display layer.

In other features, the at least one ambient light sensor includes only asingle ambient light sensor.

In other features, the at least one ambient light sensor includesambient light sensors.

In other features, the at least one ambient light sensor is integratedin the display layer and is disposed within an outer periphery of thedisplay layer.

In other features, each of the at least one ambient light sensor isdisposed between two of the light emitting diodes of the array of lightemitting diodes.

In other features, the at least one ambient light sensor is in a samelayer of the smart glass display as the display layer and is disposedoutside of a periphery of the display layer.

In other features, the at least one ambient light sensor includesexterior ambient light sensors and one or more interior ambient lightsensors.

In other features, the control module includes: a comparator configuredto obtain, based on the output of the at least one ambient light sensor,a brightness level; a vehicle message transceiver configured to obtainan image to display on the display layer; and an address driverconfigured to adjust brightness of at least a portion of the displaylayer based on the brightness level and drive the display layer todisplay the image.

In other features, the control module includes: a comparator configuredto obtain a dimming level based on the output of the at least oneambient light sensor; a vehicle message transceiver configured to obtainan image to display on the display layer; an address driver configuredto drive the display layer to display the image; and a shading driverconfigured to drive the suspended particle devices to adjust thetransparency level of at least the portion of the smart glass displaybased on the dimming level.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description, the claims and the drawings. Thedetailed description and specific examples are intended for purposes ofillustration only and are not intended to limit the scope of thedisclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1A is a cross-sectional side view of an example window withintegrated smart glass display including a single exterior ambient lightsensor according to the present disclosure;

FIG. 1B is a front view of the window of FIG. 1A;

FIG. 2A is a side cross-sectional side view of an example window withintegrated smart glass display including multiple exterior ambient lightsensors disposed within a perimeter of a display layer according to thepresent disclosure;

FIG. 2B is a front view of the window of FIG. 2A;

FIG. 3A is a side cross-sectional side view of an example window withintegrated smart glass display including multiple exterior ambient lightsensors disposed outside of a perimeter of a display layer according tothe present disclosure;

FIG. 3B is a front view of the window of FIG. 3A;

FIG. 4A is a side cross-sectional side view of an example window withintegrated smart glass display including multiple exterior ambient lightsensors and an interior ambient light sensor according to the presentdisclosure;

FIG. 4B is a front view of the window of FIG. 4A;

FIG. 5 is a functional block diagram of an example of a contrast controlsystem for a smart glass display according to the present disclosure;

FIG. 6 is a functional block diagram of an example auto-shading look-uptable (LUT) calibration system according to the present disclosure;

FIG. 7 illustrates a contrast control method according to the presentdisclosure;

FIG. 8 illustrates an auto-shading calibration method according to thepresent disclosure;

FIG. 9 is an example of a display including exterior and interiorambient light sensors according to the present disclosure;

FIG. 10 is a side cross-sectional view of an auto-shading layer in atransparent mode according to the present disclosure;

FIG. 11 is a side cross-sectional view of the auto-shading layer of FIG.10 in a dimming mode according to the present disclosure;

FIG. 12 is an example of a display including an array of light emittingdiodes (LEDs), rows of suspended particle devices (SPDs), and exteriorand interior ambient light sensors according to the present disclosure;

FIG. 13 is an example of a display including an array of light emittingdiodes (LEDs), rows and columns of suspended particle devices (SPDs),and exterior and interior ambient light sensors according to the presentdisclosure;

FIG. 14 is a side cross-sectional view of combined display andauto-shading layer in a transparent mode including LEDs and/or ambientlight sensors according to the present disclosure;

FIG. 15 is a side cross-sectional view of the combined display andauto-shading layer of FIG. 14 in a dimming mode according to the presentdisclosure; and

FIG. 16 is a front view of a window including an integrated smart glassdisplay including another pattern of ambient light sensors according tothe present disclosure.

In the drawings, reference numbers may be reused to identify similarand/or identical elements.

DETAILED DESCRIPTION

The present disclosure relates to a display devices able to operate intransparent and non-transparent modes with high contrast ratios. Whilethe foregoing description relates to display devices and systems forvehicles, the display devices and systems described herein areapplicable in other applications such as residential homes, commercialbuildings, computer games, etc. The examples disclosed herein areapplicable to automotive glass and non-automotive glass includingarchitectural glass. The examples may be applied to any window of avehicle including front, side and back windows, sunroofs and moon roofs.

A display device can be made transparent by arranging selectivelytransparent spaces between pixels of the display device and controllingthe transparency or opacity thereof. Smaller scale display technologiessuch as micro light emitting diodes (LEDs) have more opportunity to makehigher transparency display devices. However, the higher transparency ofthe display device reduces the contrast ratio due to undesired lightingfrom surroundings. For example, when the display is exposed to highambient light conditions such as sunlight, readability worsens.

Auto-shading devices can be used to change light transmittance fromtransparent to opaque by applying voltage to embedded electrodes or notapplying voltage to the embedded electrodes. This allows the backgroundof an image to be darkened to adjust the contrast ratio of the image.Examples of auto-shading technologies include suspended particle devicesand/or electrochromic devices. Outer transparent layers of glass or filmare separated by spacers. Transparent conductive coatings or layers arearranged on inwardly facing surfaces of the outer transparent layers.Suspended particles are located between the conductive coatings orlayers. When the voltage is applied to the electrodes, the particlesalign with the applied field and the corresponding portions aretransparent. When the voltage is not applied to the electrodes, theparticles return to their original orientation and the correspondingportions are opaque. Various levels of transparency may be provided byvarying the voltages.

The smart glass display devices (or simply “smart glass displays”)according to the present disclosure provide high selective contrastratios relative to other transparent display devices. Locally disposedambient light sensors are integrated in the smart glass displays and areused for selective global and local control over contrast ratios. Thisincludes adjusting contrast ratios of specific cells and/or zones of thesmart glass displays. Each cell may include one or more LEDs (or LEDtransistor circuits) and each zone may include one or more cells.

Methods are disclosed herein for automatically adjusting smart glassdisplay brightness (or intensity) and auto-shading levels based onsignals from laminated ambient light sensors. Control algorithms areimplemented to change display brightness levels and auto-shading levelsof the corresponding smart glass display based on exterior and interiorlighting conditions. By being integrated in the smart glass displays,the laminated ambient light sensors measure light levels directly infront of and/or behind the smart glass display. Smart glass displaycontrol systems provide localized and global brightness and auto-shadinglevel control of the smart glass displays. In some examples, multipleexterior ambient light sensors and one or more interior ambient lightsensors are integrated into the smart glass displays. Auto-shadinglayers are included in the smart glass displays to locally controlauto-shading levels. In some examples and depending on the layerstack-up and arrangement of the smart glass display, a dimming levelcalibration method is implemented to calibrate interior ambient lightsensor(s) including determining the true interior ambient light levelsand compensating for set auto-dimming levels.

By incorporating the ambient light sensors in the smart glass displays,the smart glass displays are not over or under driven based on ambientlighting conditions which is a concern for readability of a transparentdisplay. The ambient light sensors provide an accurate measurement ofambient light levels on the smart glass displays. This is unlike asystem that includes ambient light sensors in front of or above aninterior cabin of a vehicle or located within an interior cabin of avehicle, such as on a dashboard. Ambient light sensors in theselocations do not provide accurate ambient light measurements for use incontrolling brightness levels and/or auto-shading levels of transparentdisplays.

FIGS. 1A-1B show a window 100 with integrated smart glass display 102including a single exterior ambient light sensor 104. The window 100includes a front (or exterior) glass layer 106 and a back (or interior)glass layer 108. The smart glass display 102 includes a display layer110 and an auto-shading layer 112, which are disposed between the glasslayers 106, 108. A first resin layer 114 may be disposed between thefront glass layer 106 and the display layer 110. The ambient lightsensor 104 and the display layer 110 may be disposed on and connected toa substrate 116. The auto-shading layer 112 includes a transparencycontrol layer 120 disposed between two resin layers 122, 124. Theauto-shading layer 112 is disposed between the substrate 116 and theback glass layer 108. As an example, the resin layers 114, 122, 124 maybe formed of polyvinyl butyral (PVB).

Exterior ambient light, represented by arrow 126, is detected by theambient light sensor 104. A control module 130 receives an ambient lightsignal from the ambient light sensor 104 and adjusts a brightness levelof the display layer 110 and/or a dimming level of the auto-shadinglayer 112 via the transparency control layer 120. This may beaccomplished by adjusting voltages supplied to the display layer 110 andthe auto-shading layer 112. This is described in further detail below.The ambient light sensor 104 may be disposed anywhere around theperiphery of the display 102 or may be integrated in the display layer110, as further described below.

In this example, the single embedded ambient light sensor 104 is usedfor global control of the brightness of the display layer 110 and thedimming of the auto-shading layer 112. In some embodiments, the exampleof FIGS. 1A-1B are applied to side windows of a vehicle. This controlmay be used to save power consumed in displaying images by decreasingbrightness levels in darker ambient lighting conditions. Brightness maybe increased when conditions call for increased brightness levels, suchas when the window 100 is facing the sun.

The display layer 110 may be an exterior facing or an interior facingdisplay layer 110. In an embodiment, the display layer 110 displays animage to a person external to a vehicle, which includes the window 100.In an embodiment, the display layer 110 displays an image to a personinternal to a vehicle, which includes the window 100.

FIGS. 2A-2B show a window 200 with integrated smart glass display 202including multiple exterior ambient light sensors 204 disposed within aperimeter of a display layer 205. The window 200 includes a front (orexterior) glass layer 206 and a back (or interior) glass layer 208. Thesmart glass display 202 includes the display layer 205 and anauto-shading layer 212, which are disposed between the glass layers 206,208. A first resin layer 214 may be disposed between the front glasslayer 206 and the display layer 205. The ambient light sensors 204 anddisplay layer 205 are disposed on and connected to a substrate 216. Theauto-shading layer 212 includes a transparency control layer 220disposed between two resin layers 222, 224. The auto-shading layer 212is disposed between the substrate 216 and the back glass layer 208. Asan example, the resin layers 214, 222, 224 may be formed of PVB.

Exterior ambient light, represented by arrows 226, is detected by theambient light sensors 204. A control module 230 receives ambient lightsignals from the ambient light sensors 204 and adjusts one or morebrightness levels of the display layer 205 and/or one or more dimminglevels of the auto-shading layer 212 via the transparency control layer220. This is described in further detail below. The ambient lightsensors 204 may be disposed anywhere within the periphery of the displaylayer 205.

Although a particular number of ambient light sensors 204 are shown, anynumber of ambient light sensors may be included. In one embodiment, amatrix (or array) of ambient light sensors are included. Each of theambient light sensors 204 may have corresponding areas 240, withinwhich, for example, brightness levels of LEDs and/or a dimming level ofa portion of the auto-shading layer 212 are set based on the output ofthat ambient light sensors 204. For example, brightness levels of LEDsof the display layer 205 within one of the areas 240 may be the same andset directly based on the output of the ambient light sensor associatedwith that area. A dimming level of the portion of the auto-shading layer212 directly adjacent to and opposing the area of the ambient lightsensor associated with that area may be directly set based on the outputof that ambient light sensor. Brightness levels of other areas (i.e.areas of the display layer 205 that are between the areas 240) anddimming levels of other areas of the auto-shading layer 212 (i.e. areasnot adjacent and opposite the areas 240) may be set based on outputs ofthe ambient light sensors 204 using interpolation, triangulation,weighting, etc. Ambient light levels in areas outside the areas 240 maybe estimated and brightness levels and dimming levels are then set basedon the estimated ambient light levels.

The display layer 205 may be an exterior facing or an interior facingdisplay layer 205. In an embodiment, the display layer 205 displays animage to a person external to a vehicle, which includes the window 200.In an embodiment, the display layer 205 displays an image to a personinternal to a vehicle, which includes the window 200.

The example of FIGS. 2A-2B include a multi (or matrix) embedded ambientlight sensor display device that allows for estimating ambient lightlevels experienced across the display layer 205. The control module 230may perform triangulation to determine locations of selected points onthe display layer 205 that are between the ambient light sensors 204.The locations of the ambient light sensors 204 are known and may be usedto determine locations of the selected points. Ambient light levels atthese points may be estimated using interpolation, distances between thepoints and the ambient light sensors, and based on the ambient lightlevels measured by the ambient light sensors 204. This information maybe used to provide more accurate data for global dimming control or toperform localized diming control based on detailed exterior ambientlight conditions across the display layer 205. The smart glass display202 is thus able to be locally or segmentally brightened and/or dimmedto account for non-uniform lighting conditions.

The inclusion of multiple ambient light sensors provides more accuratedata for improved global and/or localized brightness and/or dimmingcontrol. The multiple ambient sensors may be used for: localized ambientlight measurements; verifying accuracy of each of the ambient lightsensors; and/or backing up data collected from each of the ambient lightsensors. For example, if a first ambient light sensor is detecting ahigh level of light and a second ambient light sensor is detecting a lowlevel of light, opposite brightness and dimming actions may be performedin a first area around the first ambient light sensor than brightnessand dimming actions performed in an area around the second ambient lightsensor. As another example, if the four ambient light sensors near theperiphery (or corners) of the display layer 205 detect a high level ofambient light and the center located ambient light sensor detects a lowlevel of light, then it is likely that the center ambient light sensoris operating inappropriately. Localized brightness and dimming controlmay be performed to compensate for detected light “hot spots” and glare.For example, brightness in one or more zones of the display layer 205may be increased to overcome light from nearby street lamps, which arecausing one or more bright spots on the front glass layer 206 anddisplay layer 205.

FIGS. 3A-3B show a window 300 with integrated smart glass display 302including multiple exterior ambient light sensors 304 disposed outsideof a perimeter of a display layer 305. The window 300 includes a front(or exterior) glass layer 306 and a back (or interior) glass layer 308.The smart glass display 302 includes the display layer 305 and anauto-shading layer 312, which are disposed between the glass layers 306,308. A first resin layer 314 may be disposed between the front glasslayer 306 and the display layer 305. The ambient light sensors 304 andthe display layer 305 may be disposed on and connected to a substrate316. The auto-shading layer 312 includes a transparency control layer320 disposed between two resin layers 322, 324. The auto-shading layer312 is disposed between the substrate 316 and the back glass layer 308.As an example, the resin layers 314, 322, 324 may be formed of PVB.

Exterior ambient light, represented by arrows 326, is detected by theambient light sensors 304. A control module 330 receives ambient lightsignals from the ambient light sensors 304 and adjusts one or morebrightness levels of the display layer 305 and/or one or more dimminglevels of the auto-shading layer 312 via the transparency control layer320. This is described in further detail below. The ambient lightsensors 304 may be disposed external to and around a periphery of thedisplay layer 305.

Each of the ambient light sensors 304 may be used to estimate ambientlight levels at points across the display layer 305. Brightness levelsof areas of the display layer 305 and dimming levels of areas of theauto-shading layer 312 may be set based on outputs of the ambient lightsensors 304 using interpolation, triangulation, weighting, etc. Ambientlight levels in areas of the display layer 305 that are away from theambient light sensors 304 may be estimated and brightness levels anddimming levels are then set based on the estimated ambient light levels.

The display layer 305 may be an exterior facing or an interior facingdisplay layer 305. In an embodiment, the display layer 305 displays animage to a person external to a vehicle, which includes the window 300.In an embodiment, the display layer 305 displays an image to a personinternal to a vehicle, which includes the window 300.

FIGS. 4A-4B show a window 400 with integrated smart glass display 402including multiple exterior ambient light sensors 404 and an interiorambient light sensor 407. The window 400 includes a front (or exterior)glass layer 406 and a back (or interior) glass layer 408. The smartglass display 402 includes a display layer 410 and an auto-shading layer412, which are disposed between the glass layers 406, 408. A first resinlayer 414 may be disposed between the front glass layer 406 and thedisplay layer 410. The ambient light sensors 404 and 407 and the displaylayer 410 may be disposed on and connected to a substrate 416. Theauto-shading layer 412 includes a transparency control layer 420disposed between two resin layers 422, 424. The auto-shading layer 412is disposed between the substrate 416 and the back glass layer 408. Asan example, the resin layers 414, 422, 424 may be formed of PVB.

Exterior ambient light, represented by arrows 426, is detected by theambient light sensors 404. Interior ambient light, represented by arrows428, is detected by the ambient light sensors 407. A control module 430receives ambient light signals from the ambient light sensors 404, 407and adjusts one or more brightness levels of the display layer 410and/or one or more dimming levels of the auto-shading layer 412 via thetransparency control layer 420. This is described in further detailbelow. The exterior ambient light sensors 404 may be disposed within aperiphery of the display layer 410, as shown, or disposed external toand around a periphery of the display layer 410. The interior ambientlight sensor 407 may be disposed external to and along the periphery ofthe display layer 410 or may be disposed within a periphery of thedisplay layer 410.

Although a particular number of exterior ambient light sensors and aparticular number of interior ambient light sensors are shown, anynumber of each may be included. Since the variance in exterior ambientlight across the display layer 410 can be high and the variance ininterior ambient light across the display layer 410 is typicallyminimal, fewer interior ambient light sensors (e.g., 1-2) than exteriorlight sensors (e.g., 1-10) may be included. The interior ambient lightsensors allow the control module 430 to detect when, for example, aninterior room or cabin is brightly lit up by the sun or other sources oflight and compensate for that by adjusting the contrast ratio(s) of thesmart glass display.

Each of the ambient light sensors 404, 407 may be used to estimateambient light levels at points across the display layer 410. Brightnesslevels of areas of the display layer 410 and dimming levels of areas ofthe auto-shading layer 412 may be set based on outputs of the ambientlight sensors 404 using interpolation, triangulation, weighting, etc.Ambient light levels in areas of the display layer 410 that are awayfrom the ambient light sensors 404 may be estimated based on the outputsof the ambient light sensors 404 and brightness levels and dimminglevels are then set based on the estimated ambient light levels. Bygathering information on interior and exterior ambient lighting directlyat the smart glass display 402 allows for adjusting brightness andauto-shading to provide high contrast ratios across the smart glassdisplay 402. If the display layer 410 is outward facing and the interiorof the vehicle is bright, brightness levels of the display layer 410 maybe increased and dimming levels of the auto-shading layer 412 may beincreased to increase the contrast ratio(s) of the smart glass display402 for improved viewing of an image displayed on the display layer 410.

The display layer 410 may be an exterior facing or an interior facingdisplay layer 410. In an embodiment, the display layer 410 displays animage to a person external to a vehicle, which includes the window 400.In an embodiment, the display layer 410 displays an image to a personinternal to a vehicle, which includes the window 400.

The interior ambient light sensor and/or additional interior ambientlight sensors may be incorporated in the examples of FIGS. 1A-3B.

FIG. 5 shows a contrast control system 500 for a smart glass display502. The smart glass display 502 may be implemented as any of the smartglass displays disclosed herein (e.g., any of the smart glass displaysof FIGS. 1A-4B, 9, 12-13 and 16 and/or variations thereof). The contrastcontrol system 500 includes a control module 504, which may replaceand/or operate similarly as any of the other control modules disclosedherein, a memory 506 and a power source 507. The control module 504 mayinclude a general purpose input/output (GPIO) interface 510, a firstcomparator 512, a vehicle message transceiver 514, a LED address driver516 and a shading driver 518. The smart glass display 502 may includelaminated glass (not shown), a LED display layer 520, an auto-shadinglayer 522, one or more exterior ambient light sensors 524, and one ormore interior ambient light sensors 526. The memory 506 may store one ormore brightness and/or dimming look-up tables (LUTs) 530 (or database).The brightness and dimming LUTs relate ambient light levels tobrightness and dimming levels. A vehicle bus and/or communicationinterface 532 may be included and communicate with the vehicle messagetransceiver 514. Operation of the contrast control system 500 is furtherdescribed below with respect to the method of FIG. 7 . The power source507 may include a battery pack and be a stand-alone power source or mayreceive power from an external power source. The power source 507 mayreceive utility power.

FIG. 6 shows an auto-shading LUT calibration system 600. Theauto-shading LUT calibration system 600 may include the shading driver518, the one or more interior ambient light sensors 526, a secondcomparator 602, a memory 604 and the memory 506. The second comparator602 may be implemented in the control module 504 of FIG. 5 . The memory604 and the memory 506 may be implemented together as a single memory.The memory 604 may store a calibration table, such as that shown belowas Table 1, where N is an integer. The calibration table may relateauto-shading levels to multipliers. This may include global and/or localmultipliers. The memory 506 may store a dimming LUT 608, which may be aportion of or separate from a brightness and dimming LUT. Operation ofauto-shading LUT calibration system 600 is further described below withrespect to the method of FIG. 7 .

TABLE 1 Auto-shading Level to Multiplier Conversion Auto-shading LevelMultiplier M_(i) ASL₁ M₁ ASL₂ M₂ ASL₃ M₃ . . . . . . ASL_(N) M_(N)

FIG. 7 shows a contrast control method. Although the followingoperations are primarily described with respect to the contrast controlsystem 500 of FIG. 5 , the operations are applicable to the otherembodiments disclosed herein. The following operations may beiteratively performed. The method may begin at 700.

At 702, exterior and/or interior ambient light levels are detected viathe sensors 524, 526. The GPIO interface 510 may receive signals fromthe one or more exterior ambient light sensors 524 and/or the one ormore interior ambient light sensors 526. This may include receivingsignals from any of the ambient light sensors shown in FIGS. 1A-4B, 9,12-13 and/or referred to herein.

At 704, the control module 504 may determine whether auto-shading is ON.If yes, operation 706 may be performed, otherwise operation 708 may beperformed. At 706, the control module 504 may perform an auto-shadingLUT calibration method, as described below with respect to FIG. 8 .

At 708, the first comparator may compare the exterior and interiorambient light levels to one or more brightness and dimming LUT(s) toprovide one or more brightness levels and/or one or more dimming levels.The brightness levels are provided to the vehicle message transceiver514 and/or the LED address driver 516. The dimming levels are providedto the shading driver 518. The control module 504 and/or the comparator512 may determine a brightness profile across the smart glass displayand set the brightness levels and/or the dimming levels accordingly toprovide high contrast ratios across the smart glass display.

At 710, the vehicle message transceiver 514 receives an image to bedisplayed on the LED display layer 520, which may be any of the displaylayers shown and/or described with respect to FIGS. 1A-4B, 9 and 12-13 .As a few examples, images to be displayed may be obtained by the controlmodule 504, received from the vehicle bus and/or communication interface532, and/or obtained from a memory (e.g., the memory 506). The imagesmay be for advertising, ride-hailing, and/or communication purposes. Theimages may be for individuals outside or inside of a vehicle.

At 712, the LED address driver 516 drives the LED display layer 520 todisplay the images obtained by the vehicle message transceiver 514 andbased on the brightness levels received from the first comparator 512and/or the vehicle message transceiver 514.

At 714, the shading driver 518 generates auto-shading signals to controlSPDs of the auto-shading layer 522 based on the dimming levels receivedfrom the shading driver. The dimming levels received from the firstcomparator 512 at the shading driver 518 are converted to auto-shadinglevels and/or output voltages that are provided to the SPDs of theauto-shading layer 522. The auto-shading levels are used to set a levelsof transparency or tint levels of cells and/or zones of the auto-shadinglayer. Each cell may include one or more SPDs and each zone may includeone or more cells. Operation 714 may be performed while operation 712 isperformed. Operation 702 may be performed subsequent to operations 712,714.

FIG. 8 shows an auto-shading calibration method. Although the followingoperations are primarily described with respect to the auto-shading LUTcalibration system 600 of FIGS. 5-6 , the operations are applicable tothe other embodiments disclosed herein. The following operations may beiteratively performed. Although the following operations are describedwith respect to a single un-calibrated interior ambient light level UL,a single auto-shading level and a single calibrated interior ambientlight level CL, the operations may be performed for multipleun-calibrated interior ambient light levels from multiple ambient lightsensors and/or multiple auto-shading levels for multiple zones toprovide multiple calibrated interior ambient light levels.

The method may begin at 800. At 802, an un-calibrated interior ambientlight level UL are detected respectively via one of the interior ambientlight sensors 526.

At 804, the shading driver 518 may obtain one or more initial, previous,and/or default auto-shading levels i. At 806, the second comparator 602determines a multiplier M based on the auto-shading level i, where i isan integer. The second comparator 602 may compare the auto-shading leveli to other auto-shading levels in Table 1 to determine the multiplier M.

At 808, the second comparator 602 generates a calibrated interiorambient light level CL. The calibrated interior ambient light level CLmay be generated using equation 1.CL=UL×Mi, where M≥1  (1)

At 810, the second comparator 602 updates the dimming LUT 608 in thememory 506, which may then be used by the shading driver 518 whenadjusting a dimming level of the auto-shading layer 522. The method mayend at 812 subsequent to operation 810.

The method of FIG. 8 compensates for when an auto-shading layer isdisposed between (i) a display layer, which includes an interior ambientlight sensor, and (ii) a background of the smart glass display and/or arear glass layer of the smart glass display. The background may refer toan interior of a vehicle for an outward facing display or an exterior ofthe vehicle for an inward facing display. When in this arrangement andwhen auto-shading is active, the interior ambient light sensor may notdetect the actual interior ambient light level due to the dimming of theauto-shading layer. The method of FIG. 8 increases the un-calibratedinterior ambient light level to the calibrated interior ambient lightlevel based on the level of dimming to provide an estimate of the actualinterior ambient light level. When the display layer and theauto-shading layer are integrated into a single layer as shown in FIGS.12-13 , the method of FIG. 8 may not be performed.

FIG. 9 shows a display 900 including exterior ambient light sensors 902and an interior ambient light sensor 904. The display 900 includes adata line 908, a scan line 910, and an array of light emitting diodes(LED) transistor circuits 912-11, . . . , and 912-NM, where N and M areintegers (collectively LED transistor circuits 912) where N and M areintegers. A display controller (or control module) 950 communicates withthe data line 908 and the scan line 910. Electrodes 930 and 932 connectthe data line 908 and scan line 910 to the LED transistor circuits 912.The display controller 950 executes a display application thatselectively provides power to the LED transistor circuits 912. The LEDtransistor circuits may each include a LED, a transistor and/or otherpassive circuit elements.

The color of each of the LEDs of the LED transistor circuits 912 can bedisplayed in an on/off mode or at varying intensities between fully onand fully off. In the example shown, the LEDs of the LED transistorcircuits 912 in each row vary in color (e.g. red, green and blue andthen repeat) to form pixels. In some examples, the display 900 formspart of a windshield, rear glass, side windows, instrument panel,infotainment display, rearview mirror or other window or display.

While an N×M rectangular array is shown, non-uniform layouts can be usedwith other shapes. Selectively transparent spaces corresponding to SPDsin another layer (not shown), such as one of the auto-shading layers inFIGS. 1A-4B. The selectively transparent spaces can be configured to betransparent to opaque depending upon applied voltage to SPD electrodesas will be described further below.

The display controller 950 is configured to run the display application952 that controls the LED transistor circuits 912 and SPD electrodes ofthe display 900 based on outputs of the sensors 902, 904. The displayapplication 952 also controls power supplied to the SPD electrodes. Insome examples, the display application 952 selectively controls switchesto apply voltage to the SPD electrodes that determine whether or not theselectively transparent spaces are transparent or opaque based on senseddata such as ambient light conditions or other information.

FIGS. 10-11 show an auto-shading layer 1000 of a transparent displaydevice respectively in a transparent mode (auto-shading off) and adimming mode (auto-shading on). The dimming mode provides differentlevels of transparency and may be referred to as a non-transparent oropaque mode when the dimming level is high and no light is passingthrough the auto-shading layer 1000. The auto-shading layer 1000 mayreplace one of the auto-shading layers of FIGS. 1A-4B.

The auto-shading layer 1000 includes suspended particles. In someexamples, the auto-shading layer 1000 includes a display side 1006adjacent a display layer (not shown) and an opposite side 1008. Theauto-shading layer 1000 may include one or more zones 1010 (three zones1010 a-c are shown) with the same or different levels of transparency(or dimming). Any number of zones may be included.

The auto-shading layer 1000 includes transparent layers 1014 and 1016that are spaced apart by a predetermined distance in a directiontransverse to a viewing direction of the auto-shading layer 1000. Insome examples, the transparent layers 1014 and 1016 are made of glass,transparent resin film or other transparent material. In some examples,the zones 1010 are spaced apart by spacers 1022.

In the zones 1010, transparent conductive coatings or layers 1020 and1024 are arranged in a pattern on inner, facing surfaces of thetransparent layers 1014 and 1016. Suspended particles 1028 are locatedbetween the conductive coatings or layers 1020 and 1024. A displaycontroller (or control module) selectively applies a voltage across theconductive coatings or layers 1020 and 1024 to change a level oftransparency of the selectively zones 1010.

When a voltage potential is applied across the transparent conductivecoatings or layers 1020 and 1024, the suspended particles align with theapplied field and the selectively transparent region 1010 will betransparent as shown in FIG. 10 . When the voltage potential is removed,the suspended particles 1028 return to a disordered state and theselectively transparent region 1010 will be obscured by the suspendedparticles 1028 as shown in FIG. 11 .

In some examples, the suspended particles include crystals that areabout 0.3 to 0.5 microns (μm) in length, although other types ofparticles can be used. The crystals act as induced dipoles when anelectric field is applied to the conductive coatings or layers in thefilm. When the electric field is applied, the crystals line up and allowlight to pass through. When the electric field is removed, the naturaltendency of the crystals is to be misaligned due to Brownian movement.The misaligned crystals cause the glass to tint.

Auto-shading activation can be controlled based upon the occurrence ofone or more events. For example, auto-shading can be transparent whenmeasured ambient light sensed by ambient light sensors is less than apredetermined threshold and opaque when the ambient light is greaterthan the predetermined threshold. In other examples, auto-shading can beactivated or deactivated in response to the presence or absence of anoccupant inside the vehicle. Auto-shading can be activated ordeactivated when the vehicle is started or in motion. For example, theauto-shading is deactivated when ambient light or interior light is toodim or nobody is in the car for interior facing display applications.

FIG. 12 shows a display 1200 including an array of LED transistorcircuits 1212, rows of suspended particle devices (SPDs) 1216, exteriorambient sensors 1202, and an interior ambient light sensor 1204. Thedisplay 1200 includes a data line 1208, a scan line 1210, and an arrayof LED transistor circuits 1212-11, . . . , and 1212-NM, where N and Mare integers (collectively LED transistor circuits 1212) where N and Mare integers. A display controller 1250 communicates with the data line1208 and the scan line 1210. Electrodes 1230 and 1232 connect the dataline 1208 and scan line 1210 to the LED transistor circuits 1212 andSPDs 1216-1, 1216-2, . . . 1216-N (collectively SPDs 1216) between firstrows of the LED transistor circuits 1212. The LED transistor circuits1212 are arranged in rows. The SPDs are arranged in second rows and areeach disposed between adjacent pairs of the first rows. A displaycontroller 1250 executes a display application 1252 that selectivelyprovides power to the LED transistor circuits 1212 and/or to the SPDs1216.

The color of each of the LEDs of the LED transistor circuits 1212 can bedisplayed in an on/off mode or at varying intensities between fully onand fully off. In the example shown, the LEDs of the transistor circuits1212 in each row vary in color (e.g. red, green and blue and thenrepeat) to form pixels. In some examples, the display 1200 forms part ofa windshield, rear glass, side windows, instrument panel, infotainmentdisplay, rearview mirror or other window or display.

While an N×M rectangular array is shown, non-uniform layouts can be usedwith other shapes. Selectively transparent spaces corresponding to theSPDs 1216 are arranged between the LED transistor circuits 1212. Theselectively transparent spaces can be configured to be transparent toopaque depending upon applied voltage to the SPDs as will be describedfurther below. As will be described further below, the selectivelytransparent spaces and the LED transistor circuits 1212 are arranged inthe same plane located between transparent layers as will be describedfurther below in FIGS. 14-15 .

FIG. 13 shows a display 1300 including an array of LED transistorcircuits 1362, rows and columns of suspended particle devices (SPDs)1366, exterior ambient light sensors 1302, and an interior ambient lightsensor 1304. The LED transistor circuits 1362 and SPDs 1366 alternate inboth row and/or column directions. The display 1300 include a data line1308, a scan line 1310, an array of LED transistor circuits 1362-11,1362-12, . . . , and 1362-NM (collectively LED transistor circuits 1362)and an array of SPDs 1366-11, 1366-12, . . . , and 1366-NM (collectivelySPDs 1366). Electrodes 1330 and 1332 connect the data line 1308 and scanline 1310 to the LED transistor circuits 1362 and SPDs 1366. In each rowand/or column, the LED transistor circuits 1362 alternate with the SPDs1366. In some examples, adjacent rows are aligned with each other oroffset from each other to create an alternating pattern in each row andcolumn. A display controller 1350 executes a display application 1352that selectively provides power to the LED transistor circuits 1362and/or to the SPDs 1366.

FIGS. 14-15 shows a combined display and auto-shading layer 1400including LED transistor circuits 1402 (one LED transistor circuit 1402is shown) and/or ambient light sensors 1404 (one ambient light sensor isshown), which may include exterior and/or interior ambient lightsensors. FIG. 14 shows the display and auto-shading layer in atransparent mode (auto-shading off). FIG. 15 shows the display andauto-shading layer in a dimming mode (auto-shading on). The display andauto-shading layer 1400 includes suspended particles arranged in spaceslocated between LED transistor circuits, ambient light sensors and/orpixels (including multiple LED transistor circuits). In some examples,the display and auto-shading layer 1400 includes a display side 1406 andan opposite side 1408. The display and auto-shading layer 1400 includesselectively transparent regions 1410 and LED/pixel regions 1412. In someexamples, the LED/pixel regions 1412 are arranged in an array and arespaced apart at regular intervals by the transparent regions, althoughnon-uniform spacing or other arrangements of pixels can be used.

The display and auto-shading layer 1400 includes transparent layers 1414and 1416 that are spaced apart by a predetermined distance in adirection transverse to a viewing direction of the display andauto-shading layer 1400. In some examples, the transparent layers 1414and 1416 are made of glass, transparent film or other transparentmaterial. In some examples, the transparent regions 1410 are spacedapart by spacers 1422 that are located between the selectivelytransparent regions 1410 and the LED/pixel regions 1412.

In the selectively transparent regions 1410, transparent conductivecoatings or layers 1420 and 1424 are arranged in a pattern on inner,facing surfaces of the transparent layers 1414 and 1416. Suspendedparticles 1428 are located between the conductive coatings or layers1420 and 1424. A display controller selectively applies a voltage acrossthe conductive coatings or layers 1420 and 1424 to change a level oftransparency of the selectively transparent regions 1410.

When a voltage potential is applied across the transparent conductivecoatings or layers 1420 and 1424, the suspended particles align with theapplied field and the selectively transparent region 1410 will betransparent as shown in FIG. 14 . When the voltage potential is removed,the suspended particles 1428 return to a disordered state and theselectively transparent region 1410 will be obscured by the suspendedparticles 1428 as shown in FIG. 15 .

The LED/pixel regions 1412 are located between the selectivelytransparent regions 1410. Each of the LED/pixel regions 1412 includesone or more electrodes 1472 on which is disposed the LED transistorcircuits 1402 and the ambient light sensors 1404. For example only, eachof the LED/pixel regions 1412 may have LED transistor circuits includingrespectively red, green and blue LEDs.

FIG. 16 shows a window 1600 including an integrated smart glass display1602 including another example pattern of exterior ambient light sensors1604, which may be arranged in an array across a surface of the smartglass display 1602 and have respective zones 1608. The smart glassdisplay 1602 may be configured similarly as other smart glass displaysdisclosed herein and include a display layer and an auto-shading layer.The display layer and the auto-shading layer may be integrated into asingle layer or may be separate layers. The display layer may includethe exterior ambient light sensors 1604 and an interior ambient lightsensor 1610.

The displays referred to herein may include mini LEDs, micro LEDs,organic light emitting diodes (OLEDs), and/or other light sources. Theambient light sensors referred to herein may be implemented asphototransistors and laminated in glass. The exterior ambient lightsensors referred to herein are outward facing sensors. The interiorambient light sensors referred to herein are inward facing sensors. Theglass layers referred to herein may include laminated glass. Byincorporating the ambient light sensors in a same layer as a displaylayer, the examples disclosed herein minimize the number of layersstacked to form a smart glass display and ease manufacturing. It iseasier to incorporate the sensors in a layer that includes circuitelements as opposed to another layer that is passive and does notinclude circuit elements.

The examples disclosed herein allow for global and local adjustment ofbrightness levels and auto-shading levels to control transparency andcontrast ratios of displays for improved visualization of displayedimages. Global adjustment refers to adjusting a brightness level of anentire display layer and/or adjusting an auto-shading level of an entireauto-shading layer. Local adjustment refers to adjusting brightnesslevels of cells and/or zones differently of a display layer and/oradjusting auto-shading levels of cells and/or zones differently of anauto-shading layer. This holds true when the display layer and theauto-shading layer are integrated together as a single layer.

The foregoing description is merely illustrative in nature and is in noway intended to limit the disclosure, its application, or uses. Thebroad teachings of the disclosure can be implemented in a variety offorms. Therefore, while this disclosure includes particular examples,the true scope of the disclosure should not be so limited since othermodifications will become apparent upon a study of the drawings, thespecification, and the following claims. It should be understood thatone or more steps within a method may be executed in different order (orconcurrently) without altering the principles of the present disclosure.Further, although each of the embodiments is described above as havingcertain features, any one or more of those features described withrespect to any embodiment of the disclosure can be implemented in and/orcombined with features of any of the other embodiments, even if thatcombination is not explicitly described. In other words, the describedembodiments are not mutually exclusive, and permutations of one or moreembodiments with one another remain within the scope of this disclosure.

Spatial and functional relationships between elements (for example,between modules, circuit elements, semiconductor layers, etc.) aredescribed using various terms, including “connected,” “engaged,”“coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and“disposed.” Unless explicitly described as being “direct,” when arelationship between first and second elements is described in the abovedisclosure, that relationship can be a direct relationship where noother intervening elements are present between the first and secondelements, but can also be an indirect relationship where one or moreintervening elements are present (either spatially or functionally)between the first and second elements. As used herein, the phrase atleast one of A, B, and C should be construed to mean a logical (A OR BOR C), using a non-exclusive logical OR, and should not be construed tomean “at least one of A, at least one of B, and at least one of C.”

In the figures, the direction of an arrow, as indicated by thearrowhead, generally demonstrates the flow of information (such as dataor instructions) that is of interest to the illustration. For example,when element A and element B exchange a variety of information butinformation transmitted from element A to element B is relevant to theillustration, the arrow may point from element A to element B. Thisunidirectional arrow does not imply that no other information istransmitted from element B to element A. Further, for information sentfrom element A to element B, element B may send requests for, or receiptacknowledgements of, the information to element A.

In this application, including the definitions below, the term “module”or the term “controller” may be replaced with the term “circuit.” Theterm “module” may refer to, be part of, or include: an ApplicationSpecific Integrated Circuit (ASIC); a digital, analog, or mixedanalog/digital discrete circuit; a digital, analog, or mixedanalog/digital integrated circuit; a combinational logic circuit; afield programmable gate array (FPGA); a processor circuit (shared,dedicated, or group) that executes code; a memory circuit (shared,dedicated, or group) that stores code executed by the processor circuit;other suitable hardware components that provide the describedfunctionality; or a combination of some or all of the above, such as ina system-on-chip.

The module may include one or more interface circuits. In some examples,the interface circuits may include wired or wireless interfaces that areconnected to a local area network (LAN), the Internet, a wide areanetwork (WAN), or combinations thereof. The functionality of any givenmodule of the present disclosure may be distributed among multiplemodules that are connected via interface circuits. For example, multiplemodules may allow load balancing. In a further example, a server (alsoknown as remote, or cloud) module may accomplish some functionality onbehalf of a client module.

The term code, as used above, may include software, firmware, and/ormicrocode, and may refer to programs, routines, functions, classes, datastructures, and/or objects. The term shared processor circuitencompasses a single processor circuit that executes some or all codefrom multiple modules. The term group processor circuit encompasses aprocessor circuit that, in combination with additional processorcircuits, executes some or all code from one or more modules. Referencesto multiple processor circuits encompass multiple processor circuits ondiscrete dies, multiple processor circuits on a single die, multiplecores of a single processor circuit, multiple threads of a singleprocessor circuit, or a combination of the above. The term shared memorycircuit encompasses a single memory circuit that stores some or all codefrom multiple modules. The term group memory circuit encompasses amemory circuit that, in combination with additional memories, storessome or all code from one or more modules.

The term memory circuit is a subset of the term computer-readablemedium. The term computer-readable medium, as used herein, does notencompass transitory electrical or electromagnetic signals propagatingthrough a medium (such as on a carrier wave); the term computer-readablemedium may therefore be considered tangible and non-transitory.Non-limiting examples of a non-transitory, tangible computer-readablemedium are nonvolatile memory circuits (such as a flash memory circuit,an erasable programmable read-only memory circuit, or a mask read-onlymemory circuit), volatile memory circuits (such as a static randomaccess memory circuit or a dynamic random access memory circuit),magnetic storage media (such as an analog or digital magnetic tape or ahard disk drive), and optical storage media (such as a CD, a DVD, or aBlu-ray Disc).

The apparatuses and methods described in this application may bepartially or fully implemented by a special purpose computer created byconfiguring a general purpose computer to execute one or more particularfunctions embodied in computer programs. The functional blocks,flowchart components, and other elements described above serve assoftware specifications, which can be translated into the computerprograms by the routine work of a skilled technician or programmer.

The computer programs include processor-executable instructions that arestored on at least one non-transitory, tangible computer-readablemedium. The computer programs may also include or rely on stored data.The computer programs may encompass a basic input/output system (BIOS)that interacts with hardware of the special purpose computer, devicedrivers that interact with particular devices of the special purposecomputer, one or more operating systems, user applications, backgroundservices, background applications, etc.

The computer programs may include: (i) descriptive text to be parsed,such as HTML (hypertext markup language), XML (extensible markuplanguage), or JSON (JavaScript Object Notation) (ii) assembly code,(iii) object code generated from source code by a compiler, (iv) sourcecode for execution by an interpreter, (v) source code for compilationand execution by a just-in-time compiler, etc. As examples only, sourcecode may be written using syntax from languages including C, C++, C#,Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl,Pascal, Curl, OCaml, Javascript®, HTML5 (Hypertext Markup Language 5threvision), Ada, ASP (Active Server Pages), PHP (PHP: HypertextPreprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, VisualBasic®, Lua, MATLAB, SIMULINK, and Python®.

What is claimed is:
 1. A smart glass display comprising: a first glasslayer of a window of a vehicle; a second glass layer of the window; adisplay layer disposed between the first glass layer and the secondglass layer and comprising an array of light emitting diodes and atleast one ambient light sensor, wherein the at least one ambient lightsensor is configured to detect a level of ambient light at the displaylayer, and wherein the at least one ambient light sensor comprises oneor more outer ambient light sensors and an inner ambient light sensor,the one or more outer ambient light sensors are disposed at an outerperiphery of the display layer, and the inner ambient light sensor isdisposed at a center of the display layer; an auto-shading layercomprising suspended particle devices each of which configured toselectively provide a plurality of different levels of transparency,wherein the auto-shading layer is configured to transition betweendifferent levels of transparency such that the smart glass display andcorresponding portion of the window transition between different levelsof transparency including transitioning between a transparent state, anopaque state, and one or more intermediate states, the one or moreintermediate states being more transparent than the opaque state andless transparent than the transparent state; and a control moduleconfigured to i) determine an actual ambient light level of an areainternal to the vehicle based on an output of an interior ambient lightsensor and a level of auto-shading of the auto-shading layer, wherein amultiplier is determined based on the level of auto-shading, and theactual ambient light level is generated based on the multiplier and theoutput of the interior ambient light sensor, ii) based on the actualambient light level, adjust a transparency level of at least a portionof the auto-shading layer, iii) use triangulation to determine locationsof one or more selected points between the one or more outer ambientlight sensors and the inner ambient light sensor, iv) estimate anambient light level at the one or more selected points, and v) based onthe estimated ambient light levels at the one or more selected points,adjust at least one of a brightness level of a respective portion of thedisplay layer and an auto-dimming level of a respective portion of theauto-shading layer.
 2. The smart glass display of claim 1, wherein: thecontrol module is configured to, based on an output of each of the atleast one ambient light sensors, adjust at least one of a brightnesslevel of a respective portion of the display layer and an auto-dimminglevel of a respective portion of the auto-shading layer, wherein atleast one of i) the brightness levels of the respective portions of thedisplay layer are different, and ii) the auto-dimming levels of therespective portions of the auto-shading layer are different.
 3. Thesmart glass display of claim 1, wherein one of the at least one ambientlight sensor is integrated in the display layer and is disposed withinan outer periphery of the display layer.
 4. The smart glass display ofclaim 1, wherein the at least one ambient light sensor is disposedbetween light emitting diodes of the display layer.
 5. The smart glassdisplay of claim 1, wherein the at least one ambient light sensor is ina same layer of the smart glass display as the display layer and isdisposed outside of a periphery of the display layer.
 6. The smart glassdisplay of claim 1, wherein: the at least one ambient light sensorcomprises a plurality of exterior ambient light sensors and one or moreinterior ambient light sensors; and the control module is configured toadjust the transparency level based on an output of each of theplurality of exterior ambient light sensors and the one or more interiorambient light sensors.
 7. The smart glass display of claim 6, wherein:the display layer is an outward facing display layer such that an imagedisplayed on the display layer is visible on an exterior side of thesmart glass display; and the display layer faces outward such that theimage is visible on an exterior of the vehicle.
 8. The smart glassdisplay of claim 6, wherein: the display layer is an inward facingdisplay layer such that an image displayed on the display layer isvisible on an interior side of the smart glass display; and the displaylayer faces inward such that the image is visible from an interior ofthe vehicle.
 9. The smart glass display of claim 1, wherein the controlmodule is configured to: obtain, based on the output of the at least oneambient light sensor, a brightness level; obtain an image to display onthe display layer; and adjust brightness of at least a portion of thedisplay layer based on the brightness level and drive the display layerto display the image.
 10. The smart glass display of claim 1, whereinthe control module is configured to: obtain a dimming level based on theoutput of the at least one ambient light sensor; obtain an image todisplay on the display layer; drive the display layer to display theimage; and drive the auto-shading layer to adjust the transparency levelof at least the portion of the auto-shading layer based on the dimminglevel.
 11. A smart glass display comprising: a first glass layer; asecond glass layer; a display layer disposed between the first glasslayer and the second glass layer and comprising an array of lightemitting diodes and at least one ambient light sensor, wherein the atleast one ambient light sensor includes one or more outer ambient lightsensors and an interior ambient light sensor, the one or more outerambient light sensors are disposed at an outer periphery of the displaylayer, and the interior ambient light sensor is disposed at a center ofthe display layer and being configured to detect a level of ambientlight at the display layer, the level of ambient light being indicativeof or related to an actual ambient light level of an area internal to avehicle and inward from the smart glass display; an auto-shading layercomprising suspended particle devices each of which configured toselectively provide a plurality of different levels of transparency; anda control module configured i) based on an output of the at least oneambient light sensor, to adjust a transparency level of at least aportion of the auto-shading layer, and to adjust a dimming level basedon an auto-shading level and an output of the interior ambient lightsensor to compensate for the level of auto-shading, and ii) determinethe actual ambient light level based on the output of the interiorambient light sensor and the level of auto-shading, wherein a multiplieris determined based on the level of auto-shading, and the actual ambientlight level is generated based on the multiplier and the output of theinterior ambient light sensor; wherein the control module is configuredto i) use triangulation to determine locations of one or more selectedpoints between the one or more outer ambient light sensors and theinterior ambient light sensor, ii) estimate an ambient light level atthe one or more selected points, and iii) based on the estimated ambientlight levels at the one or more selected points, adjust at least one ofa brightness level of a respective portion of the display layer and anauto-dimming level of a respective portion of the auto-shading layer.12. A smart glass display comprising: a first glass layer of a window ofa vehicle; a second glass layer of the window; a display layer disposedbetween the first glass layer and the second glass layer and comprisingan array of light emitting diodes, a plurality of suspended particledevices, and at least one ambient light sensor, wherein the at least oneambient light sensor is configured to detect a level of ambient light atthe display layer, and wherein the suspended particle devices are eachconfigured to selectively provide a plurality of different levels oftransparency, wherein the display layer is configured to transitionbetween the plurality of different levels of transparency such that thesmart glass display and a corresponding portion of the window transitionbetween different levels of transparency including transitioning betweena transparent state, an opaque state, and one or more intermediatestates, the one or more intermediate states being more transparent thanthe opaque state and less transparent than the transparent state, andwherein the at least one ambient light sensor comprises one or moreouter ambient light sensors and an inner ambient light sensor, the oneor more outer ambient light sensors are disposed at an outer peripheryof the display layer, and the inner ambient light sensor is disposed ata center of the display layer; and a control module configured to i)determine an actual ambient light level of an area internal to thevehicle based on an output of an interior ambient light sensor and alevel of auto-shading of the display layer, wherein a multiplier isdetermined based the level of auto-shading, and the actual ambient lightlevel is generated based on the multiplier and the output of theinterior ambient light sensor, ii) based on the actual ambient lightlevel, adjust a transparency level of at least a portion of theauto-shading layer, iii) use triangulation to determine locations of oneor more selected points between the one or more outer ambient lightsensors and the inner ambient light sensor, iv) estimate an ambientlight level at the one or more selected points, and v) based on theestimated ambient light levels at the one or more selected points,adjust at least one of a brightness level of a respective portion of thedisplay layer and an auto-dimming level of a respective portion of thedisplay layer.
 13. The smart glass display of claim 12, wherein each ofthe at least one ambient light sensor is disposed between two of thelight emitting diodes of the array of light emitting diodes.
 14. Thesmart glass display of claim 12, wherein the at least one ambient lightsensor is in a same layer of the smart glass display as the displaylayer and is disposed outside of a periphery of the display layer. 15.The smart glass display of claim 12, wherein the at least one ambientlight sensor comprises a plurality of exterior ambient light sensors andone or more interior ambient light sensors.
 16. The smart glass displayof claim 12, wherein the control module is configured to: obtain, basedon the output of the at least one ambient light sensor, a brightnesslevel; obtain an image to display on the display layer; and adjustbrightness of at least a portion of the display layer based on thebrightness level and drive the display layer to display the image. 17.The smart glass display of claim 12, wherein the control module isconfigured to: obtain a dimming level based on the output of the atleast one ambient light sensor; obtain an image to display on thedisplay layer; drive the display layer to display the image; and drivethe plurality of suspended particle devices to adjust the transparencylevel of at least the portion of the smart glass display based on thedimming level.
 18. The smart glass display of claim 1, wherein thecontrol module is configured to perform at least one of global and localdimming based on the estimated ambient light levels at the one or moreselected points.
 19. The smart glass display of claim 1, wherein thecontrol module is configured to adjust at least one of the brightnesslevel and the auto-dimming level to compensate for hot spots based onoutputs of the one or more outer ambient light sensors.
 20. The smartglass display of claim 1, wherein the control module is configured todetect a fault with the inner ambient light sensor based on outputs ofthe one or more outer ambient light sensors.